Drawing on contemporary archival and manuscript sources, Marc Baer unfolds the most fascinating story of Sultan Mehmed IV. Although his reign was remarkably long (1648-87), he has almost been forgot- ten or depicted dismissively as weak and foolish. Aiming to retrieve that lost history, the book’s central theme is conversion – of Muslims to “proper” Islamic practices, of Christians and Jews to Islam, and of space. Thus, the reader encounters the Kadızadeli movement that first rose to prominence in the 1650s.